In an electric drive machine, heat is produced by some components during operation. This heat is dissipated by means of a cooling liquid. The heat absorbed by the cooling liquid is released to the surroundings, as a result of which the cooling medium cools down again and can once more dissipate heat from the heat-producing components.
Electric drive machines have electrical coils with windings. The windings are arranged in grooves of a main body. The main body may also be referred to as a stator lamination pack. The windings often produce a large part of the heat and therefore have to be cooled particularly well. The windings are therefore often flowed around directly by a (cooling liquid, for example an oil, in order to achieve particularly good heat transfer from the windings to the cooling liquid. The grooves must then be sealed off with respect to the rotor chamber in order to prevent cooling liquid from exiting into the rotor chamber. Moreover, the main body has to be electrically insulated with respect to the windings in order to ensure the correct function of the electric drive machine.
Devices for electrically insulating the main body and for sealing off the grooves with respect to the stator are known from the prior art. EP 1 542 336 A1 U.S. Patent App. Pub. No. 20050151429, which are incorporated by reference herein in their entirety, discloses a paper insulation for the grooves and a sealing strip for closing off the grooves after the insertion of the windings. EP 1 768 230 B1/U.S. Patent App. Pub. No. 2007052317, which are incorporated by reference herein, and EP 1 372 242 B1 U.S. Pat. No. 7,975,370, which are incorporated by reference herein, disclose that the openings of the grooves are sealed off by means of plastic closures. The grooves are electrically insulated by plastic insulations.